2 Vocabulary fusion evaporation freezing condensation mixture Did

2 Vocabulary fusion evaporation freezing condensation mixture Did you know ? Salt is collected in these salt gardens where seawater is evaporated in large shallow basins by solar heat. 112

Did you know ? Air is a mixture of 11 different gases. 113

1 How Does Water Change? One Way That Water Changes You will need ice cubic lamp a piece of cloth clock about some ways to make an ice cubic 1 Write melt faster. 2 Plan an investigation for two of the ways. Carry out your plan. 3 Record the time it takes each ice cubic to melt. 4 Communicate to a classmate which way melted the ice cubic faster. CAUTION Science Skill You can plan an investigation to see which way works the best. Don’t touch the bulb of the lamp. 114

How water can change? Water can be a solid, a gas, or a liquid. Water as a solid may be ice or snow. Water as a gas is water vapor. In this picture, heat from the Earth is changing water from one state into another. 115

Adding Heat Changes Water Adding heat can make water change from one state of matter into another. Ice is water in its solid state. When ice is heated, it fuses and changes to a liquid. The change from a solid to a liquid is called fusion. What is fusion? when does ice fuse? 116

When water gets hot enough, it boils. When water boils, it evaporates. It changes to water vapor, like the water in the kettle. The change of state from liquid to gas is called evaporation. What makes liquid water change into a gas? 117

Taking away heat change water Cooling can also change the state of water. When water is cooled enough, it freezes, or becomes a solid called ice. The change of water from liquid to a solid is freezing. 118

When water vapor cools, it condenses and change into liquid. The change of matter from gas to liquid is called condensation. Clouds are formed of water droplets and may fall as rain. How did the cloud form? Think About it 1. What are three states of water? 2. What can make water change its state? 119

2 You will need How Does Matter Change? A mixture ½ cup of warm water spoon salt pan 1 Add one tablespoon of salt to the water and mix well 2 Pour the salt and water mixture into the pan. 3 Put the pan a warm place. Predict what will happen. 4 Observe in two days. Did you predict correctly. Science Skill You can predict, you use what you know to make a good guess. 120

Other Way Matter Changes Matter can change in different ways. How was the matter in this mixture changed? 121

Cutting and Shaping Matter Cutting is one way you can change matter. This loaf of bread has been cut into slices. The slices have a different shape from the loaf, but they are the same bread. Bending is another way you can change the shape of matter. The shape of the dough changes, but it is still dough. 122

Mixing Matter When you put different kinds of matter together, you make a mixture. A mixture is something made up of two or more kinds of things. What kinds of things are in the jar ? is this a mixture? 123

You can mix together some kinds of things and then separate them. Each thing would still be the same as it was before. How can you separate the paper clips from the other kinds of matter in this mixture? 123

Burning and Cooling Some changes to matter cannot be undone and matter changed back to how it was before. Fire and high heat often cause such changes to matter. Burning causes wood to change to ashes, gases, and smoke. The ashes, gases, and smoke cannot de changed back to wood 124

Cooking makes an egg change from a liquid to a solid. It also changes the eggs color, texture, and taste. A cooked egg cannot be changed back to raw egg. How did the egg change? Think About it 1. What changes when you cut an object? 2. What happens when you mix many kinds of matter? 3. What are some change in matter that cannot be undone and matter changed back to how it was before? 125